The graph illustrates how often and how strongly the wind blows from different directions over a normal May. The longest spokes point in the directions the wind most commonly blows from and the shade of blue implies the strength, with deep blue strongest. It is based on 1736 NWW3 forecasts of wind since since 2007, at 3hr intervals, for the closest NWW3 model node to Rockpiles, located 35 km away (22 miles). There are too few recording stations world wide to use actual wind data. Without question some coastal places have very localized wind effects that would not be predicted by NWW3.
According to the model, the prevailing wind at Rockpiles blows from the S. If the rose diagram shows a close to circular outline, it means there is no strong bias in wind direction at Rockpiles. On the other hand, dominant spokes illustrate favoured directions, and the more the darkest shade of blue, the stronger the wind. Spokes point in the direction the wind blows from. During a typical May, the model suggests that winds are light enough for the sea to be glassy (pale blue) about 19% of the time (6 days each May) and blows offshore 25% of the time (8 days in an average May). Over an average May winds exceeding >40kph (25mph) are not expected, but 2 have winds on the range 30-40 (19-25) at Rockpiles
IMPORTANT: Beta version feature! Swell heights are open water values from NWW3. There is no attempt to model near-shore effects. Coastal wave heights will generally be less, especially if the break does not have unobstructed exposure to the open ocean.